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Guess what??? Just got my error messages last week. I got both a fuel system malfunction and a drive train malfunction at the same time. While I sat there in the car parked, it started to studder with the rpm needle bouncing up and down, finally the car died. then the check engine light came on. Shut down car and called SA, he said that it probably is not related to Dinan ( I just got dinan S2 about three weeks ago). Went back to work, started car at night drove home with check engine light on, performance seem normal. Got home, shut car down and restarted, check engine light gone. Now this was a week ago, the problem had not come back and car feels strong. Regardless, car going in tomorrow for diagnosing.

Beside that, the car is amazing when dinan S2, now needs some new springs.

Dealer kept car over night, still "searching", drove 1.5 hour back home in a 2012 528 non sport, boy do I miss my 550 with Dinan S2. On another note, the turbo 4 is not that bad on the highway, in town driving...a little sluggish. Waiting....

"Reduced Power" code/indicator often comes on with no noticeable power loss, other times it feels like HPFP is gone. With my latest incident it was difficult to maintain 75mph on a flat road - passing was out of the question.

Well sports fans, this morning I got my car back after six days. The verdict on the problem was permanent fuel injector malfunctions on all cylinders. As a result, they replaced all of my fuel injectors. We will see if this was in fact the cause of the problem. I'm not so sure. I certainly hope it was.

It sure is great to get back in the 550xi after six days in a runflat tired 535. Besides the runflat tires which seem to ruin the ride I certainly noticed a very strong throttle lag delay. The car I had was an early build 2011. Also I didn't really appreciate the extent of the traction advantage of the 4 Wheel Drive until I drove this rearwheel drive 535. On a number of occasions when accelerating both from a light and up some steep hills, the traction control light in the 535 came on cutting power. Basically that has never happened to me on the 550xi.

Well sports fans, this morning I got my car back after six days. The verdict on the problem was permanent fuel injector malfunctions on all cylinders. As a result, they replaced all of my fuel injectors. We will see if this was in fact the cause of the problem. I'm not so sure. I certainly hope it was.

Great to hear you got your car back. Were the fuel injectors replaced on BMW or Dinan's dime? I could see the argument that the tune runs the fuel injectors at higher cycle duty thus causing the failure.

Good luck - hope that the problem is solved. Word of caution however - BMW initially replaced my injectors and the problem persisted. They subsequently replaced the fuel pump. I was told it has nothing to do with the software.

Good luck - hope that the problem is solved. Word of caution however - BMW initially replaced my injectors and the problem persisted. They subsequently replaced the fuel pump. I was told it has nothing to do with the software.

They tested the fuel pump and claim that it's output was normal. I would guess that the Dinan tune has the entire engine working harder than normal. I forget how blindingly fast the car was until I got back in

Great to hear you got your car back. Were the fuel injectors replaced on BMW or Dinan's dime? I could see the argument that the tune runs the fuel injectors at higher cycle duty thus causing the failure.

I don't know who paid. But I sure am glad I got my tune from a BMW dealer who is also a dinan dealer

The injectors being swapped out has nothing to do with Dinan. That's an issue some F10's have and there are actually updated fuel injectors that are out now if you have an issue with your current setup. My friend has a stock 2012 550xi and he had all his swapped out.

BMW dealers that are Dinan dealers are obligated by their Dinan franchise agreement to help any Dinan customer regardless of which Dinan dealer tuned the car.

Good to know. I didn't know that. Of course when I come, my client advisor, who is M Certified, a major performance lover and has Dinan mods on his 3 Series, always comes down to help even on service issues. Honestly with the several Dinan mods I've gotten from them, the dealership and service department treat me like a king. That's why they gave me the 535i sport as a loaner car instead of a three series.

The injectors being swapped out has nothing to do with Dinan. That's an issue some F10's have and there are actually updated fuel injectors that are out now if you have an issue with your current setup. My friend has a stock 2012 550xi and he had all his swapped out.

Interesting, do you know it those updated fuel injectors were also changed on the factory line at some point during the 2012 run?

Obviously after your friends. Do you know what month his 2012 was produced?

The injectors being swapped out has nothing to do with Dinan. That's an issue some F10's have and there are actually updated fuel injectors that are out now if you have an issue with your current setup. My friend has a stock 2012 550xi and he had all his swapped out.

Good to know! My car was produced in late December 2011 or early January 2012

Well sports fans, this morning I got my car back after six days. The verdict on the problem was permanent fuel injector malfunctions on all cylinders. As a result, they replaced all of my fuel injectors. We will see if this was in fact the cause of the problem. I'm not so sure. I certainly hope it was.

I had the same diagnosis issues with my Stg 3 mod'd '08 335Xi. They started by replacing some of the injectors, next it was the rest of the injectors and the ignition coils, then it was the wastegate acutators, then the fuel pump, and finally both turbochargers.

I hope you're not about to head down this same nightmarish diagnostic path

I had the same diagnosis issues with my Stg 3 mod'd '08 335Xi. They started by replacing some of the injectors, next it was the rest of the injectors and the ignition coils, then it was the wastegate acutators, then the fuel pump, and finally both turbochargers.

I hope you're not about to head down this same nightmarish diagnostic path

I sure hope not. But if it gets anywhere near that I will be trying to lemon the car. I Certainly hope that doesn't happen because I love the car

Dealer kept car over night, still "searching", drove 1.5 hour back home in a 2012 528 non sport, boy do I miss my 550 with Dinan S2. On another note, the turbo 4 is not that bad on the highway, in town driving...a little sluggish. Waiting....

Got my car back over weekend. Below is what they found, they did open an case with BMW for any future problems. For now, the car feels very strong with Dinan S2, just hope that this really fixed the problem.

Got my car back over weekend. Below is what they found, they did open an case with BMW for any future problems. For now, the car feels very strong with Dinan S2, just hope that this really fixed the problem.

So all they did was replace the low pressure sensor? On Dinan or BMW's dime?